On Fri, Oct 24, 2014 at 01:59:19PM +0200, Thomas Petazzoni wrote:
> This commit adds the implementation of ->suspend() and ->resume()
> platform_driver hooks in order to save and restore the state of the
> GPIO configuration. In order to achieve that, additional fields are
> added to the mvebu_gpio_chip structure.
>
> Signed-off-by: Thomas Petazzoni <[email protected]>
> Cc: Linus Walleij <[email protected]>
> Cc: Alexandre Courbot <[email protected]>
> Cc: [email protected]
> ---
> drivers/gpio/gpio-mvebu.c | 99
> +++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 99 insertions(+)
>
> diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c
> index 418e386..dd5545c 100644
> --- a/drivers/gpio/gpio-mvebu.c
> +++ b/drivers/gpio/gpio-mvebu.c
> @@ -83,6 +83,14 @@ struct mvebu_gpio_chip {
> int irqbase;
> struct irq_domain *domain;
> int soc_variant;
> +
> + /* Used to preserve GPIO registers accross suspend/resume */
> + u32 out_reg;
> + u32 io_conf_reg;
> + u32 blink_en_reg;
> + u32 in_pol_reg;
> + u32 edge_mask_regs[4];
> + u32 level_mask_regs[4];
> };
>
> /*
> @@ -554,6 +562,93 @@ static const struct of_device_id mvebu_gpio_of_match[] =
> {
> };
> MODULE_DEVICE_TABLE(of, mvebu_gpio_of_match);
>
> +static int mvebu_gpio_suspend(struct platform_device *pdev, pm_message_t
> state)
> +{
> + struct mvebu_gpio_chip *mvchip = platform_get_drvdata(pdev);
> + int i;
> +
> + mvchip->out_reg = readl(mvebu_gpioreg_out(mvchip));
> + mvchip->io_conf_reg = readl(mvebu_gpioreg_io_conf(mvchip));
> + mvchip->blink_en_reg = readl(mvebu_gpioreg_blink(mvchip));
> + mvchip->in_pol_reg = readl(mvebu_gpioreg_in_pol(mvchip));
> +
> + switch (mvchip->soc_variant) {
> + case MVEBU_GPIO_SOC_VARIANT_ORION:
> + mvchip->edge_mask_regs[0] =
> + readl(mvchip->membase + GPIO_EDGE_MASK_OFF);
> + mvchip->level_mask_regs[0] =
> + readl(mvchip->membase + GPIO_LEVEL_MASK_OFF);
> + break;
> + case MVEBU_GPIO_SOC_VARIANT_MV78200:
> + for (i = 0; i < 2; i++) {
> + mvchip->edge_mask_regs[i] =
> + readl(mvchip->membase +
> + GPIO_EDGE_MASK_MV78200_OFF(i));
> + mvchip->level_mask_regs[i] =
> + readl(mvchip->membase +
> + GPIO_LEVEL_MASK_MV78200_OFF(i));
> + }
> + break;
> + case MVEBU_GPIO_SOC_VARIANT_ARMADAXP:
> + for (i = 0; i < 4; i++) {
> + mvchip->edge_mask_regs[i] =
> + readl(mvchip->membase +
> + GPIO_EDGE_MASK_ARMADAXP_OFF(i));
> + mvchip->level_mask_regs[i] =
> + readl(mvchip->membase +
> + GPIO_LEVEL_MASK_ARMADAXP_OFF(i));
> + }
> + break;
> + default:
> + BUG();
Isn't it too severe? Is the platform going too unstable if driver
reaches this case?
I'd consider a WARN() instead.
> + }
> +
> + return 0;
> +}
> +
> +static int mvebu_gpio_resume(struct platform_device *pdev)
> +{
> + struct mvebu_gpio_chip *mvchip = platform_get_drvdata(pdev);
> + int i;
> +
> + writel(mvchip->out_reg, mvebu_gpioreg_out(mvchip));
> + writel(mvchip->io_conf_reg, mvebu_gpioreg_io_conf(mvchip));
> + writel(mvchip->blink_en_reg, mvebu_gpioreg_blink(mvchip));
> + writel(mvchip->in_pol_reg, mvebu_gpioreg_in_pol(mvchip));
> +
> + switch (mvchip->soc_variant) {
> + case MVEBU_GPIO_SOC_VARIANT_ORION:
> + writel(mvchip->edge_mask_regs[0],
> + mvchip->membase + GPIO_EDGE_MASK_OFF);
> + writel(mvchip->level_mask_regs[0],
> + mvchip->membase + GPIO_LEVEL_MASK_OFF);
> + break;
> + case MVEBU_GPIO_SOC_VARIANT_MV78200:
> + for (i = 0; i < 2; i++) {
> + writel(mvchip->edge_mask_regs[i],
> + mvchip->membase + GPIO_EDGE_MASK_MV78200_OFF(i));
> + writel(mvchip->level_mask_regs[i],
> + mvchip->membase +
> + GPIO_LEVEL_MASK_MV78200_OFF(i));
> + }
> + break;
> + case MVEBU_GPIO_SOC_VARIANT_ARMADAXP:
> + for (i = 0; i < 4; i++) {
> + writel(mvchip->edge_mask_regs[i],
> + mvchip->membase +
> + GPIO_EDGE_MASK_ARMADAXP_OFF(i));
> + writel(mvchip->level_mask_regs[i],
> + mvchip->membase +
> + GPIO_LEVEL_MASK_ARMADAXP_OFF(i));
> + }
> + break;
> + default:
> + BUG();
Ditto.
Br, David Cohen
> + }
> +
> + return 0;
> +}
> +
> static int mvebu_gpio_probe(struct platform_device *pdev)
> {
> struct mvebu_gpio_chip *mvchip;
> @@ -577,6 +672,8 @@ static int mvebu_gpio_probe(struct platform_device *pdev)
> if (!mvchip)
> return -ENOMEM;
>
> + platform_set_drvdata(pdev, mvchip);
> +
> if (of_property_read_u32(pdev->dev.of_node, "ngpios", &ngpios)) {
> dev_err(&pdev->dev, "Missing ngpios OF property\n");
> return -ENODEV;
> @@ -735,5 +832,7 @@ static struct platform_driver mvebu_gpio_driver = {
> .of_match_table = mvebu_gpio_of_match,
> },
> .probe = mvebu_gpio_probe,
> + .suspend = mvebu_gpio_suspend,
> + .resume = mvebu_gpio_resume,
> };
> module_platform_driver(mvebu_gpio_driver);
> --
> 2.0.0
>
> --
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